There's a terrific player in there, but Heung-Min Son's performance at the Stadium of Light against Sunderland summed up his predicament at Tottenham Hotspur this season.

Back in September, Son was the talk of the Premier League. He'd been on the verge of leaving Spurs in the summer, linked with a return to the Bundesliga, but Mauricio Pochettino convinced him to stay and for that month the club reaped enormous benefits.

He starred on the domestic front as well as grabbing a winner in the Champions League and was deservedly named as the Premier League Player of the Month.

However, since then the South Korean has blown hot and cold. He admitted that his travelling with the international team and niggling little injuries affected his form in those months before the turn of the year.

However, since the last international break his inconsistent performances have continued. On his day, he can be a game changer with his pace and skill. On an off day he huffs and puffs and runs a lot, but ultimately struggles to have an impact.

Despite the clinical finishes he can produce in big moments, Son is actually not a natural finisher which seems ridiculous bearing in mind he has 12 goals this season.

Before his deflected goals against Wycombe Wanderers in the FA Cup he showed just that as chances came and went, including one where the goalkeeper Jamal Blackman dropped the ball at his feet with only a defender blocking the goal.

Read More

Against Sunderland Son again threatened without ever impacting. The other problem for Son is that while Christian Eriksen and Dele Alli were equally ineffective at the Stadium of Light, perhaps more so, it was him who was hooked by Pochettino.

Heung-Min Son celebrates his goal at Manchester City

Eriksen and Alli are so fundamental to the way that Spurs play, the manager rarely removes them from the field of play, especially the Dane.

With Spurs looking so much better in a 3-4-3 formation, which brings the best out of Alli and Eriksen, could Son better serve the team as an impact sub?

When he came on against West Ham United at White Hart Lane in November he was instrumental in changing the game. He popped up with that big equaliser from the bench at Manchester City as well. The bench against Sunderland showed once again, with Erik Lamela still recovering from hip injury, the lack of game changers Tottenham have to bring on.

Throwing Son's fresh legs into the fray against tired defenders is a recipe for success almost every time, but Pochettino knows what reducing the South Korean's minutes will mean come the summer.

He was unhappy with his lack of action last season, although he was still settling into life in England, and were he to come knocking on Pochettino's door again this summer then the potential price tag might be worth cashing in this time around.

The Spurs boss must decide whether the short term gain from adding quality to his bench is worth Son's probable departure in the summer.